Because Fi BTL is God subwoofer, back in Russia, I had Fi BTL in Yugo and hit 161.xx db sealed dash with the door open. It is very powerful woofer, my yugo was stuck by lighting and BTL made bass note heard all the way in Moscow, still worked. Highly recommend this speaker one time it made a car alarm make noise when i turned it up. HCCA is girly woofer that hits 126.xx db in the port on 8k power reading, no good woofer.